Fluorescent probe for detecting activation of sialidase

Abstract

A fluorescent probe for sialidase activity detection, is a compound represented by the following general formula or a salt thereof.R1, if present, represents the same or different monovalent substituent present on a benzene ring. R2 and R3 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. R4 and R5 each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom. R6 represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms. R6′ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R6′ may form, together with R3 or R5 a five to seven-membered heterocyclyl or heteroaryl containing a nitrogen atom to which R6′ is bonded.

1 . A compound represented by a general formula (I) described below or a salt thereof: 
       
         
           
           
               
               
           
         
         wherein 
         R 1 , if present, represents the same or different monovalent substituent present on a benzene ring; 
         R 2  and R 3  each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; 
         R 4  and R 5  each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a halogen atom; 
         R 6  represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 5 carbon atoms; 
         R 6 ′ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and 
         R 6 ′ may form, together with R 3  or R 5 , a five to seven-membered heterocyclyl or heteroaryl containing a nitrogen atom to which R 6 ′ is bonded; 
         R 7  and R 8 , if present, each independently represent an alkyl group having 1 to 6 carbon atoms or an aryl group, and 
         in a case where X is an oxygen atom, R 7  and R 8  are not present; 
         R 9  in each occurrence is independently selected from a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, a hydroxyl group, a carboxyl group, a halogen atom, a sulfo group, an amino group, an alkoxycarbonyl group, or an oxo group; 
         in a case where R 10  is present, R 10  represents the same or different monovalent substituent present on a benzene ring; 
         X represents an oxygen atom, a silicon atom, or a carbon atom; 
         m is an integer of 0 to 4; 
         n is an integer of 1 to 3; 
         s is an integer of 1; and 
         t is an integer of 0 to 4. 
       
     
     
         2 . The compound or a salt thereof according to  claim 1 , wherein R 6  is —CH 2 -CF 3 . 
     
     
         3 . A fluorescent probe for sialidase activity detection, comprising the compound or a salt thereof according to  claim 1 . 
     
     
         4 . A method of detecting sialidase activity, the method comprising:
 introducing the compound or a salt thereof according to  claim 1  into a cell; and   measuring fluorescence emitted by the compound or the salt of the compound reacted with a sialidase in the cell.